Rotary well reamer



Oct. 25, 1938. w. A. ABEGG ROTARY WELL REAMER Filed. June 15, 1937 2Sheets-Sheet 1 firs/rib)" 14/94 72/? 6 625266 M/ Patented Oct. 25, 1938UNITED STATES.

ROTARY WELL mama Walter A. Abegg, IDS Angeles, Calif., minor to GlobeOil Tools Company, Los Nietos, Cali! a corporation of CaliforniaApplication June 15, 1937, Serial No. 148,301

14 Claims.

This invention relates to well drilling tools and relates moreparticularly to well reamers for use in the rotary method of welldrilling. A general object of this invention is to provide a practicaland particularly eflicient well reamer having self cleaning cutters.

The rotary well reamers now in general use generally have three rollercutters mounted at circumferentially spaced points to have 3-pointcontact with the wall of the well. The typical 3-point reamer has adecided tendency to bind or stick in the well bore, probably because itmaintains the well bit truly centralized and prevents any play orwobbling of the bit. Another undesirable feature of rotary well reamershaving roller cutters is the tendency for the cutters to become balledup or to accumulate mud that interferes with the cutting or reamingaction of the cutters.

Another object of this invention is to provide a rotary well reamer inwhich the cutters are related and arranged to have 4-point contact withthe wall of the well bore, that is, the cutters are spaced about theaxis of the reamer shank to engage the well wall at fourcircumferentially spaced points.

Another object of this invention is to provide a rotary well reamer inwhich the roller cutters are arranged in substantially diametricallyopposite pairs, the cutters of each pair being'in close relation,whereby the reamer may remain free in the well and does not drag orretard the drilling speed.

Another object of this invention is to provide a well reamer of thecharacter mentioned in which the shank is formed and the cutters arerelated to leave substantial spaces about the reamer when the same is inthe well, thereby facilitating fishing operations in the event that thereamer or the drilling string becomes lost or caught in the well.

Another and important object of this invention is to provide a wellreamer embodying rotatable cutters that are self-cleaning in operationand that do not become "bailed up with accumulations of mud. etc.

Another object of this invention is to provide a rotary well reamer inwhich the teeth or cutting parts of the adjacent cutters clearthemselves of mud, etc. by meshing one with the other without direct oractual contact.

Another object of this invention is to provide a self-cleaning reamer ofthe character mentioned in which the cutters may be identical or alike,thereby reducing the cost of manuiacture and maintenance.

Another object of this invention is to provide a well reamer of thecharacter mentioned embodying simple, effective means for mounting thepairs of identical cutters so that the cutting parts of adjacent cuttersmesh to clear the cutters of mud and the like.

A further object of this invention is to provide a well reamer of thecharacter mentioned that is simple and inexpensive to manufacture andthat embodies cutters whose teeth may be cut in a lathe.

The various objects and"features of my invention will be fullyunderstood from the following detailed description of a typicalpreferred form and application or the invention, throughout whichdescription reference is made to the accompanying drawings, in which:

Fig. 1 is a side elevation of the reamer provided by this invention.Fig. 2 is an enlarged fragmentary side elevation of the reamer providedby this invention illustrating one pair of cutters and the adjacentparts. Fig. 3 is a horizontal detailed sectional view taken as indicatedby line 3-3 on Fig. 1. Fig. 4 is an enlarged fragmentary verticaldetailed sectional view taken as indicated by line 4-4 on Fig. 3illustrating the mounting of one of the cutters. Fig. 5 is a horizontaldetailed sectional view taken as indicated by line 5--5 on Fig. 2 andFig. 6 is an enlarged fragmentary vertical detailed sectional view takensubstantially as indicated by line 6-6 on Fig. 3.

The improved well reamer provided by this invention includes, generally,a body or shank I0, four roller cutters Ii, and means I! supporting thecutters II on the shank ID in diametrically opposite pairs with thecutting parts of each pair of cutters in intermeshing relation.

The body or shank i is provided to carry the cutters H and theirsupporting means 12 and is intended to be connected in a rotary welldrilling string. The shank I0 is an elongate member provided at itsopposite ends with means for facilitating its connection in the string.In the particular case illustrated in the drawings a tapered threadedpin I3 is provided on the upper end of the shank I0 and a taperedthreaded socket [4 is provided in the lower end of the shank ID tofacilitate the connection of the shank in the drilling string. Theopposite end portions l of the shank l0 may be cylindrical and may havewickers 16 to facilitate the fishing of the reamer from the well in theevent that it becomes caught side surfaces n substantially tangential tothe peripheries of theend portions II and two side surfaces It curvedconcentric with the longitudinal axis of the shank l9 and having agreater radius of curvature than the end portions ll.

The opposite ends l9 of the flattened interme diate portion of the shankill are preferably inclined or. tapered. Recesses or pockets 29 areprovided in the intermediate portion of the shank ll to receive thecutters i l. The recesses or pockets 29 have their mouths or outer endsat the. side surfaces II and extend axially or vertically of the shankIll. There are two diametrically opposite pockets 2' and the sides ofthe pockets are open at the surfaces l1. The upper and lower walls 2| ofthe pockets 29 are preferably flat and at right angles to the axis ofthe shank II and the inner wall of ,each pocket 29 may have twovertically extending concave surfaces or'walls. as best illustrated inFig. 5 of the drawings. The shank i0 is provided with the usuallongitudinally extending passage 2| for conducting the circulationfluid.

The cutters l l are in the nature of roller reaming cutters andinaccordance with the invention the four cutters Ii may be identical.The cutters H are generally cylindrical and have fiat upper and lowerends. The lower portions of the cutters Il may be frusto-conical ortapered. A central longitudinal opening 22 extends through each cutter Hfrom one end to the other. Peripheral cutting parts are provided on thecutters I I. The cutting parts may be in the nature of teeth 22 formedby making a plurality of spaced V-shaped circumferential grooves 24 inthe peripheries of the cutters and interrupting or intersecting thecircumferential grooves 24 with axially extending grooves 25. Thegrooves 25 may be partially cylindrical in transverse cross section.When the teeth 28 are formed in this manner they occur incircumferential series separated by the V-shaped grooves 24 and theseveral teeth of each series 29 are separated by the vertical grooves25.

The means l2 for mounting or supporting the cutters II on the shank I0support two cutters II in each pocket 29, the cutters in each pocketbeing in adjacent parallel relation. The mounting means for the cuttersll may be varied considerably without departing from the broaderprinciples of the invention, that is, mounting means of various naturesmay be employed to support the cutters in the relationship contemplatedby the invention. The cutter mounting or supporting means l2 removablyor detachably support the cutters H on the shank ill and incllldesupporting pins 26 passed through the cutter openings II. The protrudingportions of the pins 26 are supported by parts removably secured to theshank Hi. The projecting portions of the cutter pins 26 are carried byblocks 21 inserted in sockets or bores 26 in the shank Ill. The cuttersII are rotatable on their pins 26 and the pins 26- are supported by theblocks 21 so that the cutters ll projectbeyond the surfaces I I to havereaming contact with the wall of the well bore. The blocks 21 arecylindrical in transverse cross section and each has a flat side surface29. The opposite ends of the blocks 21 may be flat.

The'sockets or berg 29 are shaped to accuratelyor closely receive eblocks 21. The bores 22 are cylindrical and extend transversely into theintermediate portion of the shank II from, its

sides I 9. In the particular construction illuk trated in the drawingsthere are'two bores 29 adjacent each end 2| of each pocket 29. the bores24 adjacent the ends of the sockets being in parallel relation.

In the preferred form of the invention the cutter supporting means l2are such that the cutters ll of each pair are'in slightly staggered orvertically oflset relation so'that the teeth 29 of the adjacentidentical cut yrs are in meshing relation. The adjacent b0 s 29 at theends of the pockets 26 are slightly vertically oilset, that is, thelongitudinal axes of the adjacent bores 29 are slightly oflsetvertically. The bores 29 at the ends of a pocket 29 are correspondinglyoi!- set so that the distance between the centers of the verticallyaligned bores 29 at the opposite ends of the pockets is equal. Theblocks 21 are introduced in the bores 28 from their outer ends and theinner ends of the blocks may bear against the inner walls of the bores'and the outer ends of the blocks may be flush with the sides I 9 of theshank. Each block 21 is provided with a transverse or diametric opening20. The openings receive the projecting portions of the cuttersupporting pins 26. The blocks 21 are arranged in the sockets" to havetheir flat side surfaces 29 face inwardly toward the pockets 24. Thebores 28 are spaced from the ends 2| of the pockets 29 and flat wallednotches 3| connect the ends of the pockets 20 with the bores 29. Theside surfaces 29 of the blocks 21 form side or bottom walls of thenotches 3|. Fiat sided thrust washers 32 are provided on the pins 28 andare received in the notches ii. The thrust washers 22 are held againstturning through cooperation with the walls of the notches 9| and bearagainst the surfaces 29 of the blocks 21. The thrust washers 92 areengaged by the ends of the cutters II. The washers 92 at the'corresponding ends of the cutters ii are of the same thickness. For thisreason the washers 92 cooperating with the surfaces 29 of the verticallyoffset blocks 21 support the cutters ll against endwise movement in therelationship where one cutter of each pair is slightly higher than theadjacent cutter II.

The extent of vertical offsetting of the adjacent cutters II issubstantially equal to one half of the thickness or vertical extent ofthe teeth 29. The sets or pairs of bores 28 are related so that the pins26 supported by the blocks 21 in the bores carry the cutters 'so thatthe adjacent cutters II are in the relation where their teeth 23 mate ormesh. Due to the vertical offsetting of the cutters i I described above,the cutters ll of the pairs may be supported in such close relation thattheir teeth 23 mesh throughout the major portions of their depths. It isto be understood, however, that the cutting teeth 23 of the adjacentcutters ll need not come into' direct or actual contact. Fig. 2 of thedrawings best illustrates the meshing relation of two adjacent cuttersII and the vertical offsetting ofthe cutters that permits the desiredmeshing of the cutting teeth 22.

The means I 2 include means for preventing rotation of the cuttersupporting pins 26 and for locking theblocks 21 in place. A notch 24 isprovided in one end of each pin 29 and keys 2| are welded or otherwisefixed in the openings 99 of the blocks 21 receiving .the end portions ofthe pins 26 to cooperate with the notches 34. The

iii

these spaces about the shank Ill may greatly keys 88 cooperating withthe notches 34 dependably prevent rotation of the pins 28. Openings 38extend axially in the intermediate portion of the shank ill from itsopposite ends l9 and intersect or join the bores 28 at substantiallydiametrically opposite points. The blocks 21 have notches 31 forregistering with the openings 38.

.Tapered pins 38 are arranged in the openings 36 to cooperate with thenotches 31. The pins 38 cooperating with the notches 31 positivelyprevent displacement of the blocks 21. The blocks 21 fitting thecylindrical bores 28 have no tendency to move vertically or inwardly andtheir outward movement is positively prevented by the pins 38cooperating with the notches 31. Screws 38 are threaded in the outerportions of the openings 38 to hold the pins 38 in place. It is to beunderstood that the pairs of adjacent blocks 21 of the cutter supportingmeans l2, described above, may be made integral in which case theduced'in the bores 28. With the introduction of.

the blocks 21 in the bores 28 the washers 32 are entered in the notches3|. When the blocks 21 have been properly positioned in the bores 28 thepins 38 are arranged in place to secure the blocks 21 againstdisplacement. It will be understood how the cutters Il may be easilyremoved from the shank I when it is desired to repair or recondition thereamer. When the pins 38 are withdrawn from the openings 36 the blocks21 may be easily withdrawn from the bores 28 to disconnect the cutters Hfrom the shank I0.

In the operation of the reamer provided by this invention the cutters llprojecting from the mouths of the pockets 28 engage or act on the wallof the well bore. The reamer is usually rotated in a right-handdirection as indicated by the arrow A in Fig. in which case the adjacentcutters ll rotate on their individual axes in the direction indicated bythe arrows B. From an inspection of Fig. 5 of the drawings it will beapparent that the meshing or mating teeth of the adjacent cutters llpassbetween one another while moving in opposite directions. The teeth 23thus moving one past the other efiectively clear the cutters ll of mud,etcf The longitudinal grooves 25 assure the better clearing of the mudfrom the cutters H. The engagement of the cutters H with the earthformation during the rotation of the reamer assures the independentrotation of the cutters H and as the teeth 23 of the adjacent cuttersmesh the cutters are at all times maintained free and clear ofaccumulations of mud, etc.

The cutters H are provided on the shank H) in diam etrically oppositepairs to have contact with the side wall of the well bore atfour spacedpoints. This four point engagement of the cutters with the 'earthformation is such that the reamer remains free in the well and does notbind or materially resist rotation of the drilling string. Further, thecutters ll being arranged in diametrically opposite pairs and the shankl0 being provided with the fiat side surfaces l1 provides or leavessubstantial spaces at opposite sides of the shank giving the reamergreater movement and freedom in the well. Further facilitate the fishingor removal of the reamer from the well in the event that it becomes lostor stuck. Although the cutters II are formed and mounted to mesh for thepurpose described above, they may be identical to materially reduce thecost of manufacture of the reamer. The cutters H and the wear receivingelements of the cutter supporting means l2 are easily replaceable sothat the reamer may be reconditioned when worn.

Having described a typical preferred form and application of myinvention, I do not wish to be limited or restricted to the specificdetails herein setforth, but wish to reserve to myself any variations ormodifications that may appear to those skilled in the art or fall withinthe scope of the following claims.

Having described my invention, I claim:

-1. A well reamer comprising a shank, and two substantiallydiametrically opposite pairs of roller reaming cutters on the shank, thecutters of each pair being in adjacent relation and the said pairs beingspaced substantial distances apart circumferentially of the shank.

2. A well reamer comprising a shank, and two pairs of-adjacent rollerreaming cutters rotatably supported on diametrically opposite sides ofthe shank the shank to rotate about substantially vertical axes, saidpairs of adjacent cutters being spaced substantial distances apartcircumferentially of the shank.

3. A well reamer comprising a shank, and two substantiallydiametricallyopposite pairs of roller reaming cutters on the shank, thecutters including cutting teeth, the teeth of the cuttersof each pairbeing in meshing relation.

4. A well reamer comprising a shank to be connected in a well drillingstring, a pair of roller sides of said portion.

6. A well reamer comprising a shank to be connected in a well drillingstring, roller cutters having cutting teeth, and means rotatably sup--porting the cutters in longitudinally ofiset relation with the teeth inintermeshing relation.

7 A well reamer comprising a shank to be connected in a well drillingstring, two roller cutters each having peripheral longitudinally spacedcutting teeth, and means rotatably supporting the cutters on the shankfor rotation about axes extending longitudinally of the shankand inadjacent longitudinally offset relation so that the teeth of one cutterare in intermeshing relation to the teeth of the other cutter.

8. A well reamer comprising a shank to be connected in a rotary welldrilling string and having two diametrically opposite pockets, tworoller cutters in each pocket, and supports supporting 'the cutters inthe pockets for rotation about spaced axes whereby the cutters providefourpoint engagement with the wall of the well bore.

9. A well reamer comprising a shank to be connected in a rotary welldrilling string and having two diametrically opposite pockets, tworoller cutters in each pocket, and two spaced pins passing through eachpocket each rotatably supporting a cutter whereby the cutters havefourpoint engagement with the wall of the well bore. 10. A well reamercomprising, a shank to be connected in a rotary well drilling string andhaving two diametrically opposite pockets, the sides of the-shankbetween the pockets being flattened, two roller cutters in each pocket,and

' supports supporting the cutters in the pockets I for rotation aboutspaced axes whereby the cutters provide four-point engagement with thewall oi the well bore.

11. A well reamer comprising a shank to be connected in a rotary welldrilling string and having, an external pocket, pairs of substantiallycutting parts, the cutters being vertically oflset and with theircutting parts in meshing relation.

12. 'A well reamer comprising a shank to be connected in a rotary welldrilling string and having an external pocket, pairs 01' substantiallyvertically aligned supports at the upper and lower ends'oi the pocket,the distance between the aligned supports being equal, the said pairs ofspaced supporting pins passing vertically through each pocket, meanssupporting the end portions of the pins, and cutters rotatable on thepins in adjacent relation and having cutting parts. the cutting,parts ofthe adjacent cutters being in meshing relation.

14. A well reamer comprising a shank to be connected in a rotary welldrilling string and having two diametrically opposite pockets, twospaced supporting pins passing vertically through each pocket, meanssupporting the end portions of the pins, said means including membersrem'ovably secured to the body and carrying the opposite end portions oithe pins, and cutters rotatable on the pins in adjacent relation andhaving cutting parts, the cutting parts of the adjacent cutters being inmeshing relation.

WALTER A.'ABEGG.

